As someone who has spent a LOT of time walking through low income apartments (many years ago) I know the exact smell you are referring to. With that said, I am not sure what can be done to combat the stink, if the tenants do not take care of their hygiene. Hopefully someone with come along with some contract advice on what to add to try and be proactive about it, but man I do NOT miss that smell one bit.
Create Lasting Wealth Through Real Estate
Join the millions of people achieving financial freedom through the power of real estate investing